A full on update for the iOS4 to reach 4.1 has been rumored since the iPhone 4 was first released. Finally, Apple CEO Steve Jobs has issued a glimmer of hope, saying simply, “Software update coming soon. Sent from my iPhone.”
It is widely hoped that this update will not only improve the natural reception of the iPhone 4, but will also fix the sometimes faulty proximity sensor, designed to lock down the face of the iPhone 4 when making a call. The 4.0.1 update fixed a problem with the way signal bars were calculated and the 4.0.2 update fixed a security issue that allowed users to easily jailbreak the phone.
Source: PC World